Macroscopic cross section measurements and effect detection in materials using neutron radiography technique

Neutron radiography (NR) techniques were applied to analyze behaviors of thermal neutrons in slabs having wide range of scattering to non-scattering cross section ratio r. Transmittance were measured for various materials as a basic data for NR study itself, after scattering components were estimated and subtracted from observed neutron intensities at behind of slabs. Macroscopic cross sections were estimated and were agreed with given values within ± 20 %. Defects (voids and foreign materials or impurities) were also analyzed, and their detection limits in thickness and thickness change were estimated for various r materials as a function of t. (author)